Do not optionally load C dependencies in requests (#4035)

pip/_vendor/README.rst

@@ -105,6 +105,7 @@ Modifications
 * pkg_resources has been modified to import its externs from pip._vendor
 * CacheControl has been modified to import its dependencies from pip._vendor
 * packaging has been modified to import its dependencies from pip._vendor
+* requests has been modified *not* to optionally load any C dependencies.
 
 
 Debundling

pip/_vendor/requests/__init__.py

@@ -49,11 +49,13 @@
 __copyright__ = 'Copyright 2016 Kenneth Reitz'
 
 # Attempt to enable urllib3's SNI support, if possible
-try:
-    from .packages.urllib3.contrib import pyopenssl
-    pyopenssl.inject_into_urllib3()
-except ImportError:
-    pass
+# Note: Patched by pip to prevent using the PyOpenSSL module. On Windows this
+#       prevents upgrading cryptography.
+# try:
+#     from .packages.urllib3.contrib import pyopenssl
+#     pyopenssl.inject_into_urllib3()
+# except ImportError:
+#     pass
 
 import warnings
 

pip/_vendor/requests/compat.py

@@ -21,12 +21,14 @@
 #: Python 3.x?
 is_py3 = (_ver[0] == 3)
 
-try:
-    import simplejson as json
-except (ImportError, SyntaxError):
-    # simplejson does not support Python 3.2, it throws a SyntaxError
-    # because of u'...' Unicode literals.
-    import json
+# Note: We've patched out simplejson support in pip because it prevents
+#       upgrading simplejson on Windows.
+# try:
+#     import simplejson as json
+# except (ImportError, SyntaxError):
+#     # simplejson does not support Python 3.2, it throws a SyntaxError
+#     # because of u'...' Unicode literals.
+import json
 
 # ---------
 # Specifics